1. Field of the Invention
The present invention relates to a method of determining positions of beads on a member to be subjected to a crushing load.
2. Description of the Background Art
In an automobile, for the purpose of protection of a passenger, members of a car body are equipped with beads for absorbing an energy due to a crushing load exerted to them externally.
Such beads can be positioned in various different manners. For example, for a side member 103 inside an engine room 101 of a car 100 shown in FIGS. 1 and 2, beads 105 may be provided on edges as shown in FIG. 3(A), on side faces as shown in FIG. 3(B), or on both of these as shown in FIG. 3(C). In each of these cases, when the side member 103 is subjected to a crushing load in a direction A, the beads 105 function to prevent the side member 103 from bending or cracking, and to absorb an energy due to the crushing load by making the side member 103 to be crushed along the direction A.
Now, conventionally, the positions of such beads have been determined empirically, by performing a number of tests of crushing on the member on which the beads are to be provided. However, such a manner of determining the positions of beads is not only time-consuming and expensive, but also not necessarily reliable despite of all the time and the cost.